输入:待排列的全部圆的半径R集合,圆的总数n 输出:最小圆排列距离Vmin,最优排列方案Path 算法: 1. 令Vmin为一个理论上绝对足够长的距离, Path=[] 2. 令ANode=zeros(n+1,n), ANode(1,:)=1:n, ANode(n+1,:)=1 (最后一行记录X中已确定部分数量) 3. 根据ANode(:,1)的信息计算出AVal和ABound(利用代价函数)对应的值 4. 当ANode非空时循环 5. --令AVal中最小值下标为loc, 则令X=ANode(1:n,loc), k=ANode(n+1,loc) 6. --如果ABound(loc)小于Vmin 7. ----对X(k+1)={1,2,...,n}-{X(1),X(2),...,X(k)}进行循环 8. ------如果k+1小于n, 即X(1:(k+1))为非叶结点 9. --------令lb为由X的前k+1个部分信息利用代价函数计算出的ABound的值 10. --------若lb小于Vmin,则把[X;k+1]加入ANode,把X对应的当前价值加入AVal,把lb加入Abound 11. ------否则 12. --------计算X的当前价值,并确定是否更新Vmin和Path 13. --从ANode中删去第loc列,从AVal中删去第loc个元素,从ABound中删去第loc个元素,写出其matlab程序
时间: 2024-02-09 19:11:50 浏览: 61
以下是对应的Matlab程序:
```matlab
function [Vmin, Path] = min_circle_arrange(R)
% 待排列的全部圆的半径R集合,圆的总数n
n = length(R);
% 最小圆排列距离Vmin,最优排列方案Path
Vmin = inf;
Path = [];
% 令ANode=zeros(n+1,n), ANode(1,:)=1:n, ANode(n+1,:)=1
ANode = zeros(n+1, n);
ANode(1, :) = 1:n;
ANode(n+1, :) = 1;
% 根据ANode(:,1)的信息计算出AVal和ABound(利用代价函数)对应的值
AVal = zeros(1, n);
ABound = zeros(1, n);
for j = 1:n
ANode_j = ANode(:, j);
X = ANode_j(1:n);
k = ANode_j(n+1);
[AVal(j), ABound(j)] = calculate_val_bound(X, k, R);
end
% 当ANode非空时循环
while ~isempty(ANode)
% 令AVal中最小值下标为loc, 则令X=ANode(1:n,loc), k=ANode(n+1,loc)
[min_val, loc] = min(AVal);
X = ANode(1:n, loc);
k = ANode(n+1, loc);
% 如果ABound(loc)小于Vmin
if ABound(loc) < Vmin
% 对X(k+1)={1,2,...,n}-{X(1),X(2),...,X(k)}进行循环
for i = setdiff(1:n, X(1:k))
% 如果k+1小于n, 即X(1:(k+1))为非叶结点
if k+1 < n
% 令lb为由X的前k+1个部分信息利用代价函数计算出的ABound的值
lb = calculate_bound(X(1:k+1), R);
% 若lb小于Vmin,则把[X;k+1]加入ANode,把X对应的当前价值加入AVal,把lb加入Abound
if lb < Vmin
ANode(:, end+1) = [X;i;k+1];
AVal(end+1) = calculate_val(X, i, R);
ABound(end+1) = lb;
end
% 否则
else
% 计算X的当前价值,并确定是否更新Vmin和Path
val = calculate_val(X, i, R);
if val < Vmin
Vmin = val;
Path = [X;i];
end
end
end
end
% 从ANode中删去第loc列,从AVal中删去第loc个元素,从ABound中删去第loc个元素
ANode(:, loc) = [];
AVal(loc) = [];
ABound(loc) = [];
end
end
% 计算X中第k+1个圆放置在位置i时的价值
function val = calculate_val(X, i, R)
% 已放置的圆的圆心坐标
C = zeros(length(X), 2);
% 已放置的圆的半径
r = zeros(length(X), 1);
for j = 1:length(X)
C(j, :) = [R(X(j)) + r(j), 0];
for k = 1:j-1
d = norm(C(j,:) - C(k,:));
r(j) = max(r(j), r(k) + R(X(j)) - d);
end
end
% 加上第k+1个圆
C = [C; [R(i) + r(k+1), 0]];
r = [r; R(i)];
% 计算圆排列的距离
d = 0;
for j = 1:length(X)+1
for k = j+1:length(X)+1
d = d + max(0, norm(C(j,:) - C(k,:)) - r(j) - r(k));
end
end
val = d;
end
% 计算X的前k+1个部分信息利用代价函数计算出的ABound的值
function lb = calculate_bound(X, R)
% 已放置的圆的圆心坐标
C = zeros(length(X), 2);
% 已放置的圆的半径
r = zeros(length(X), 1);
for j = 1:length(X)
C(j, :) = [R(X(j)) + r(j), 0];
for k = 1:j-1
d = norm(C(j,:) - C(k,:));
r(j) = max(r(j), r(k) + R(X(j)) - d);
end
end
% 计算圆排列的距离的下界
lb = 0;
for j = 1:length(X)
for k = j+1:length(X)
lb = lb + max(0, norm(C(j,:) - C(k,:)) - r(j) - r(k));
end
end
% 加上剩余未放置的圆的最小距离
lb = lb + calculate_min_distance(setdiff(1:length(R), X), R);
end
% 计算剩余未放置的圆的最小距离
function d = calculate_min_distance(I, R)
if isempty(I)
d = 0;
return;
end
if length(I) == 1
d = 2*R(I);
return;
end
d = inf;
for i = I
J = setdiff(I, i);
d_i = R(i) + calculate_min_distance(J, R);
if d_i < d
d = d_i;
end
end
end
```
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